Qverwind-preventing means for spring-operated devices



June 19, 1928-. 1,673,936

C A. CARLSON OVERWIND PREVENTING MEANS FOR SPRING OPERATED DEVICES Filed Jan. 5, 1927 Patented June 19, 1928.

C AXEL'CARLS O N, ROCKFORD, ILLINOIS.

OVERWIND- PREVENTING MEANS FOR SPRING-OPERATED DEVICES.

Application filedlanuary 3. 1927.. Serial No. 158,442.

- This, invention relates to spring operated device's generally and is particularly con cerned with the, provision ofa simple and practical form of means for preventing overwinding of the power spring.

According to the present invention, I provide means'for positively limiting the number of winding turns oft-he winding stem or arbor to prevent overwinding and avoid danger of breaking the spring or placing other parts of the mechanism driven thereby under an overload. I

As will presently appear, a movable part is provided arranged to move progressively toward a limit. position during the winding operation so as-to. prevent winding beyond acertain predeterminedextent.

The invention is illustrated in the accompanying drawings, wherein' 1g. 1 is a view of a watch, the cover plate Of which is removed to disclose the parts visible at, the top plate, the present invention being employed in connection with the winding wheel; I

Fi 2. is an enlarged sectional detail taken on-t e line 2-2 of Fig. 1 to show the relationship between the winding wheel and the overwinding preventing means of my invention;

Fig. 3 is a view taken on the line 33 of Fig. 2 looking in the direction of the arrows;

Fig. 4 is a view similar to Fig. 3 with the outermost plate removed to disclose the sliding plate and y I Fig.5 is still another similar view with the sliding plate removed) to show the inner plate with its spiral groove by means of which the sliding plate is moved back and forth from one limit position to another in the unwinding and winding of the main spring. I I

The same reference numerals are applied to corresponding parts throughout the views.

The present invention asstated before, contemplates application generally to all spring operated devices such as phonographs, clocks and watches, mechanical toys and; the like;

in short, wherever-it becomes desirable or expedient to prevent overwinding of the power spring. For they purposes of the present description, I have shown thelapplication of my invention to use in the works of an: ordinary watch for limiting the winding 'of' the main spring. The watch shown 1 at 6 is, forthe most part, of? the usual construction having: a top plate 7 with a winding wheel 8, and crown wheel 9. The stem 10 has the usual connection with the crown wheel to turn the winding wheel to wind the main spring; 11 (Fig. 2). One end of the main spring is fixed, as at 12, to the stem or arbor 13'bearing the winding wheel 8,.whilethe other end is suitably fixed to the main wheel 14. The main wheel meshes with the usual center pinion 15 to transmit the power of the main spring to the watch works. The winding wheel is, of course provided with the usual recoil click (not shown). This brief description will suffice to introduce the parts with which the present invention is concerned. As will presently appear, my invention provides for the limiting of the number of winding turns of the winding arbor 13 so as to prevent overwinding of the main spring 11. a

According to, the present invention, three plates, designated 16, 17, and 18 are provided, the plate 165 having the hub portion 19 receiving the arbor 13 with a drive fit so that the plate 16 turns with the arbor during winding. The plate 18 has a rim portion 20' making a drive fit about the .the two plates during winding and unwinding. As shown in Fig. 4, the plate 17 is of a double arcuate form so as to fit within the rim of the depression 2-2 at both ends of its travehthat is, in its position corresponding to the completely wound condition of the spring and that corresponding to the unwound condition of the spring. The plate 17 is guided for rectilinear. movement relative to the plate 16 by lugs 23 projecting from the plate 17 and received in radial slots 24 provided in the plate 16. A slot 25 is provided in the plate 17 between the lugs 23 to permit movement of the plate relative to the arbor 13. An arcuate lug 26 isprovided on the inner side of the plate 17 to fit in a spiral groove27 cut in the outer face of the plate 18. In the turning of the winding arbor, the plate 16 is arranged to turn the plate 17 with it and cause the lug 26 to travel from a limit position at one end of the spiral groove 27 toward the other end of said groove. The progress of the lug 26 in the groove 27 is reflected inthe travel of the lugs 23 toward the ends of the slots 24. I prefer, however, to make the slots 24 of suflicient length so that the lugs :23 will approach no closer to the endthereof than about as shown in Fig- 3, thus making end by reason of the fact that the groove has four and one-half tarps-therein, as shown in Fig. 5. I

In operation, the turning of the winding stem 10 of the watch, or other spring 0perated. device, turns the plate l6'and causes the lug 26 of the plate lF-totravel from one end of the 'spiralgroove toward the other end, by reason of thefact that the plate '17 is held for rotation with the plate 16 by the engagementof the lugs '23 in the slots 24. When" four and one-half turns of the arbor have been completed, or'whatever predetermined number is' provided for, the lug 2 6'comes into engagement with the end of the groove 27 and positively prevents further turning of the arbor. 1 It is, therefore,

impossible to overwind .the spring and the danger of breaking the spring or placing any of the driven parts under an overload is avoided. The operator, is definitely aware of the fact when he has wound up the spring to the proper extent. 1

Duringunwinding, it is obvious that the reverse from the operation above described will occun That is, the plate 16 Willievmain stationary while'the plate 18 will turn pied thereby when the main gradually with the main wheel 14 in the un winding of the spring and, therefore, cause the lug 26 to move progressively from the limit position'above referred to back toward its initial position. In the drawing the parts appear in the relative positions occuspringis substantially unwound. j I

It is'believed the'foregoing description conveys a clear understanding of the advantages of my invention and of its many possible applications. Nhile the present description has made reference to-one particular embodiment, it should be understood, as stated "above, that the invention is capable of many other embodiments as will readily appear to anyone skilled in the art The appended claims have been drawn with a View to covering all legitimate modifications, adaptations, and variations coming within the spirit and scope of the invention.

-- 4; In a spring operated Ielaim:

operated devices, comprising three plates disposedin face to face relation, the one outside platebeing connected to the middle plateby'means of one. or more lugs provided on the face of one plate engaging in one or more radial guldeways provided on the other plate, and the other outside plate being operatively connected to the middle' plate by means of a lug provided on the face of one plate engaging in a spiral guidewayprovided on the other plate, the one-outside plate being arranged to be'turned' in winding and the other outside plate being arranged to be turned in unwinding and the arrival of one of'said lugs atuthe end ofit s guideway in winding serving to prevent morethan a certain amount of winding;

I 2. In a spring operated device, the combination with a winding stem, a power spring'havingone end' thereof fixed to said stem, anda power transmitted-gear having the other end'ofsaid spring fixedthereto, of means for preventing overwinding of'said spring. comprising plate fined to turn with said stem, said plate having a radial slot therein providinga guidewa'y, a second plate guided for sliding movement on said third plate having'a spiral groove therein to provide asecond guideway, saidsecond plate having apart received in said groove whereby in the turning of said firstplat-e said second plate is moved radially 'thearrival of the second plate at one end of one of said 'guideways serving to limit the number of turns of saidste'm in winding.

3. A- structure as set forth in claim 2.

wherein the third plate is fixed with'respect to said'pow'er tr'ansmittinggear, and serves to enclose the power spring between'it and said gear, the second plate being disposed between the first and third -plate,and one of the'latter 'two' plates being recessedto enclose the second 'plate-between it and the other plate. i

device the combination of a winding stem, 'an element turned thereby in winding, another elementrelatively stationary during winding, and means comprising two inter-threading partsserving to limit'the turning of said stem, the

one part being operatedby the first element and the otherpart-being fixed with the other el ment.

' 5. An over winding prevention unit for spring operated devices comprising a pair of eoaxially arrangedmembers, the firstof which is arranged to turn with a part turnmg during winding of the spring, and the other of which. isarranged to turn 'witha part turning during unwinding of the spring, the said two members being disposed in fixed spaced relations, and a third member disposed between and operatively connected with the other two members and arranged in the turning of the first member relative to the second to move progressively to a limit position where it holds the first member against further turning and thereby prevents more than a certain amount of winding.

6. A device as set forth in claim 5 wherein the three members are flat plates, one of the first two having a radial slot therein and the other having a spiral groove, the third having a lug on one side engaging in the slot and a lug on the other side engaging in the groove.

In witness of the foregoing I afiix my signature.

0 AXEL GARLSON. 

